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Why are Input/Output filters missing in my LangSmith self-hosted deployment?

Self Hosted·2 min read·Mar 27, 2026··

Context

When migrating from LangSmith SaaS to a self-hosted deployment, you may notice that the Input/Output filter options are missing from the trace filtering interface. These filters, which allow you to search through trace inputs and outputs, may not appear in your self-hosted environment even though they were available in the SaaS version.

Answer

The Input/Output filters are missing because they rely on ClickHouse search indexing, which is automatically disabled when using LangSmith-managed ClickHouse in self-hosted deployments.

This behavior occurs when clickhouse.external.hybrid is set to true in your Helm values.yaml file. This setting:

  • Automatically disables ClickHouse search indexing (sets FF_CH_SEARCH_ENABLED=false)

  • Prevents sensitive data (inputs, outputs, errors) from being stored as searchable tokens in ClickHouse

  • Keeps that data only in your blob storage (S3/GCS) within your VPC for security

  • Hides Input/Output filter options and Full-Text Search in the UI since there's no indexed data to query

Important: Do not change clickhouse.external.hybrid to false while using LangSmith-managed ClickHouse. This flag is required for the managed ClickHouse integration to work correctly, including proper blob storage routing.

Alternative Solution: Instead of Input/Output filters, use filtering based on input/output key-value pairs. You can find more information about this approach in the LangSmith documentation on filtering traces.

Currently, there is no supported way to enable Input/Output filters while using managed ClickHouse, as the hybrid flag always overrides the search setting by design.